The present invention relates to a safety device for locks which utilizes a rotatable diaphragm interposed between the key opening and the operating portion of the lock.
There are presently known many types of so-called `safety` locks which in effect are not so inasmuch as the operating portion of the lock is easily accessible from the outside through the opening in which the key is inserted. It is for this reason that the so-called `safety` locks can be easily opened from the outside by the use of lock picks and other commonly-known burglar tools.